Electric heater



(No Model.)

C. SEILEBh? ELECTRIC HEATER.

Patented Mam. 20, 1888.

N. PUERS. Phumbahogrnpher. walhingmn, D. C.

UNITED STATES PATENT OFFICE.

CARL SEILER, OF PHILADELPHIA, PENNSYLVANIA.

ELECTRIC HEATER.

SPECIFICATION forming part of Letters Patent No. 379,822, dated March20, 1888.

Application filed December 22, 1887. Serial No. 258,672. (No model.)

To all whom t may concern.-

Be it known that I, CARL SEILEE, a citizen of the United States, and aresident of Philadelphia, Pennsylvania, have invented certainImprovements in Electric Heaters, of which the following is aspecification.

My invention relates to the production of heat by passing acurrent ofelectricity through a conductor'of high resistance; andthe object of myinvention is to provide an electric heater of this character for theproduction of heat for domestic and industrial purposes, with the Viewof getting the best possible heating effeet with the simplestconstruction.

In the accompanying drawings, Figure 1 is a plan view of my improvedelectric heater in its preferred form. Fig. 2 is a longitudinal sectionon the line 1 2, Fig. 1.

One of the-main features of my invention consists in so combining theconductor, which is to be heated to redness by the current ofelectricity passed through it, with a large ra; diating-surface ofnre-proof insulating material as to get a better heating effect than canbe obtained from the heating of the conductor alone. For this purpose Iprovide the radiating-surface with a number of projections of suitablecharacter, around and in contact with which the heating-conductors areplaced, and the radiating-surface is of such character as to be capableoi' itself becoming heated by contact of the heated conductors. As themost convenient way of constructing the radiatingsurface, I make theseprojections in the form of cones, which are preferably made detachable,as hereinafter described.

In connection with heating-coils, a regulating device isprovided tocontrol the amount of current supplied, and consequently the amount ofheat to be obtained.

In the apparatus illustrated in the accompanying drawings, A is a plateof fire-proof insulating material lying on the bottom of a shallow metaltrough, B. On this plate are the cones D, which, as I have said, arepreferably made separate or detachable from the plate A, for convenienceof repair oralterations. Like the plate A, these cones are made of amaterial which is fire-proof and an insulator of electricity, and in thecase of the cones the material must also be of such a character as to becapable of taking the heat of the conductors and of becoming red-hotwhen the conductors are heated to a red heat. The material used may beporcelain, nre-brick, or other material which will answer the requisitesnamed. A piece of Wire, E, made of platina or other suitable refractorymaterial, iswound around each one of the cones in a double spiral, asshown in the drawings. The

terminals of each coil are connected to the terminals of adjoiningcoils, preferably through the medium of metal plates F, which at thesame time separate adjoining cones from each other.

These plates F are secured in place by screws f, so that the terminalsof the wires may be thereby clamped between the plates. rI he adjoiningcoils E are preferably connected up' in series by means of these clamps,as illustrated in Fig. 1, and as many cones with their coils areemployed as the size or character of the heater may demand.

It will be understood that the radiating-surface described, instead ofbeing dat, may be curved, round, cylindrical, or of any other convenientconformation, according to the different purposes for which the heateris to be used.

In order to regulate the amount of heat to be obtained, I combine withthe heater a regulating device consisting of resistances R and acommutator, G, such as described and claimed by me in Letters Patent No.366,034. As shown in the drawings, this commutator may consist of Woodo1' any other material adapted to turn in suitable bearings and havingupon its peripheral surface metallic projections g at suitableintervals. Upon these projections are adapted to bear contact-fingers h,forming the terminals of resistance-coils or other forms of resistance,Fig. 1.

rllhe contact-finger p at one end of the com- IOC into or cut out of theshort circuit around the heating-coils and the amount of currentsupplied to the latter correspondingly controlled.

In Fig. 2 I have shown the terminals of the series coils as connected tobinding-posts b; but, il' desired, there may be combined with the rowsof coils a commutator or switch, L, similarin character to thecommutator G, and contact-nagels Z at the terminals of the rows of coilsmay be adapted to bear on the pro jections of the commutator-cylinder,so that by turning the latter more or fewer rows of coils may beincluded in the circuit, according to the amount of heat desired.

I claim as my inventionl. An electric heating device consisting ofiire-prooi' insulating material having projections around and in contactwith which heating-conductors are placed.

2. An electric heater consisting of a radiating-surface of fire-proofinsulating material, having,` conical projections around and in contactwith which heating-conductors are placed, and which are capable of beingheated by the coils.

3. An electric heater consisting of a surface of fire-proof insulating`vmaterial and detachable cones thereon and heating-conductors around thecones.

4. The combination of the surface of {ireproof insulating material,having,` detachable cones, with heating-conductors coiled on the latter,and metallic clamps for the terminals of the adjacent coils.

5. The combination of the electric heater, lineconductors, and a shortcircuit around the electric heater, with resistances and acommutator-switch in the said short circuit, as described.

6. The combination of the rows of heatingeoils and connectedcontact-fingers with a com mutator or switch to include more or fewerofthe rows of coils in circuit.

In testimony whereof I have signed my name to this specification in thepresence ol* two subscribing witnesses.

CARL SEILER.

vWitnesses:

HENRY HowsoN, HARRY SMITH.

